• Title/Summary/Keyword: hot plate methods

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Anti-depressant Effect of the Extracts of Aconitum carmichaeli (부자(附子)의 우울증 억제효과에 관한 연구)

  • Chang, Moon-Kyoo;Kim, Geun-Woo;Koo, Byung-Soo
    • Journal of Oriental Neuropsychiatry
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    • v.20 no.3
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    • pp.49-64
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    • 2009
  • Objectives : The water and methanol extracts of Aconitum carmichaeli(Aconiti Tuber Preparat) were investigated for their anti-depressant effects. Methods : In this study, reserpine-induced hypothermia test, tail suspension test and hot plate test. Additionally, the brain monoamine oxidase activity was determined in vivo. Results: In the reserpine-induced hypothermia test, both extracts suppressed the fall of body temperature compared to the control group in a dose-dependent manner, suggesting the inhibition on hypothermia. In the tail suspension test, the methanol extract dose-dependently reduced the duration of immobility by 28.4% at a dose of 1 g/kg compared to control group, which is more effective than the water extract. In the hot plate test, the water extract and methanol extract increased the jump latency time compared to the control group, showing the inhibition rate of 198% and 182%, respectively, at a dose of 1 g/kg. Methanol extracts potently inhibited the brain monoamine oxidase activity in an in vivo assay compared to the control group, showing 84.6% inhibition, but the water extract revealed very weak activity. Conclusions : Above results suggested that the extract of Aconitum carmichaeli can be useful for the prevention and treatment of depression.

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Characterization of LaCrO$_3$ Powders Synthesized by Combustion Process with Different Heating Methods (가열방법에 따른 LaCrO$_3$ 연소합성분말의 특성)

  • 정층환;박홍규;오석진;박지연
    • Journal of the Korean Ceramic Society
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    • v.35 no.10
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    • pp.1078-1084
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    • 1998
  • lanthanum chromite(LaCrO3) powder was synthesized by the combustion of a solution of metal nitrates La(NO3).6H2O and Cr(NO3)3.9H2O and urea. The pH of solution affected a yield of the combustion products but did not influence the morphology of the products. When the pH of the solution was in the range of 0.7-4, the yield of the combustion products was more than 90% The morphology of the combustion products was af-fected by heating methods for the solution. The hot-plate induced heating of the solution yielded powders hav-ing two-dimensionally interconnected agglomerates whereas microwave-induced heating produced a fine and non-agglomerated powders. The specific surface area(BET) of the combustion products using microwave-in-non-agglomerated powders. The specific surface area(BET) of the combustion products using microwave-in-duced heating method were larger(25~32m2/g) than that of hot plate heating method(10-14m2/g)

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Operating Characteristic Analysis of Optic Temperature Sensor for Overheat Detection in Panel Board (분전함에서 이상발열 감지를 위한 광온도센서의 동작특성 분석)

  • Moon, Hyun-Wook;Kim, Dong-Woo;Gil, Hyung-Jun;Kim, Dong-Ook;Lee, Ki-Yeon;Kim, Hyang-Kon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.23 no.10
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    • pp.100-106
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    • 2009
  • In this study, methods of overheat detection at the coupling or wire in electrical facility are investigated, operating characteristic about the optic temperature sensor for continuous on-line temperature monitoring in diagnostics system of electrical facility is analyzed. Heating sources in the experiment for operating characteristics of optic temperature sensor use black body and hot plate, output voltage of optic temperature sensor in accordance with temperature variation is analyzed. Overheat generation due to poor contact at the circuit breaker in panel board detects using a thermocouple, infrared thermal camera and optic temperature sensor, and experiment results are analyzed. The effect of optic temperature sensor is the same that of other methods. These results expect to use basic research material for adjusting field of electrical diagnostics system using RFID type optic temperature sensor in the near future.

A Benchmark study on the reference stress to supply fatigue analysis of welded structure (용접구조물 피로해석 적용을 위한 기준응력 비교 연구)

  • 서정관;최홍민;이제명;백점기;김명현;김현수
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.10a
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    • pp.421-428
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    • 2004
  • Various type of welded joints of the ship structure have been examined numerically and experimentally under bending and tensional cyclic constant-amplitude loading. Cyclic loading on structures can produce failures not readily predicted by conventional static analysis. The aim of a benchmark study is achieved with a generalization of the reference stress concept. Also different methods and procedures exist for the computation of the welded structure hot-spot stress a welded joints. These are either based on the extrapolation of stresses at certain reference points on the plate surface (or edge) close to the weld toe-as known from experimental investigations- or on the linearization of stresses in the through-thickness direction. In the present paper, the different methods are reviewed and applied to four different details in order to compare the methods with each other and to illustrate the differences.

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The Analgesic Effect and Its Neuropathologic Changes of Pulsed Radiofrequency Lesions in the Sciatic Nerve of the Rat (백서 좌골신경에 시행한 박동성 고주파술 (Pulsed Radiofrequency)이 급성 통증과 신경조직에 미치는 영향)

  • Lee, Kee-Heon;Shin, Keun-Man;Kweon, Kyoung-Seok;Jung, Bae-Hee;Lim, So-Young;Hong, Soon-Yong;Choi, Young-Hee;Park, Young-Euy
    • The Korean Journal of Pain
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    • v.13 no.2
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    • pp.149-155
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    • 2000
  • Background: Pulsed radiofrequency (RF) lesioning is a painless procedure and causes no neurodestruction and neuritis-like reaction are common following conventional RF lesioning. There is little data about the effect of pulsed RF especially with regard to its suitability for the treatment of acute pain. The possibility of a placebo effect cannot be ruled out because a double-blind study was not performed in previous studies. There is also no neuropathologic study about pulsed RF. Methods: The rats were anesthetized with sodium pentobarbital (40 mg/kg, i.p.; supplemented as necessary). The common sciatic nerve was exposed by blunt dissection through biceps femoris. Pulsed RF was administered to the common sciatic nerve using a 30 ms/s pulse with for 120 seconds. The temperature reached was no more than $42^{\circ}C$. Analgesia was determined using hot-plate assay shortly and, 3 days and 1 week before, and 2 weeks after operation. Lesions were examined with LM (light microscope) and EM (electron microscope) 2 weeks later. Results: There were no differences in response latencies between the control and experimental group. There were many vacuoles with hyaline bodies in the Schwann cell cytoplasm rather than axon in LM and larger electron dense bodies. No changes were found in the axon or unmyelinated fibers. Only small changes were found in the sheaths of myelinated fibers and Schwann cells. Conclusions: We therefore do think that any analgesic effect of pulsed RF is not a result of block of neural conduction. But rather than it can be attributed to others factors. It was also ineffective as a treatment for acute pain such as that caused by the hot-plate test.

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A Real Situation Experimental Study on The Thermal Protection Performance of Firefighter Clothes and Gloves (소방방화복 및 소방장갑의 열 보호 성능에 대한 실제 화재 실험 연구)

  • Lee, Won Jae;Kang, Gu Hyun;Jang, Yong Soo;Kim, Wonhee;Choi, Hyun Young;Kim, Jae Guk;Kim, MinJi;Seo, Kyo;kim, Do hee;Lee, Joo-young;Choi, Jung Yoon
    • Journal of the Korean Burn Society
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    • v.21 no.1
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    • pp.17-21
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    • 2018
  • Purpose: This study aimed to evaluate the thermal protective function of firefighter clothes and gloves through real scale fire simulations. Methods: Firstly, the fire simulation by real scale flame was performed for firefighter clothes. A manikin equipped with firefighter clothes was directly exposed to flames which energy average is 84 Kw/m2. for 22 seconds. Heat flux gauges attached on the body measured surface temperature elevation. Secondly, we also performed the other fire simulation by hot plate exposure to firefighter gloves. Firefighter gloves with heat flux gauges exposed hot plate which temperature is 300℃ in both dry and moist conditions. Primary outcome was surface temperature change of manikin body (first simulation) and hand (second simulation) over times. Results: In the first flame simulation, the surface temperature of face and shoulders elevated more rapidly comparing with the other body surface area when initial period of flame shutter open. After 18sec of shutter open, the surface temperature of upper trunk elevated rapildy. After shutter closure, high surface temperature kept continuously on right side of face and left shoulder. In the second hot plate simulation, fingers and palms showed higher surface temperature than the other areas of hands in the both dry and wet conditions. Conclusion: This study suggests that the real scale flame enables firefighter clothes to lose their heat protective function suddenly after 18 seconds. Additionally, the protective function of firefighter gloves were relatively weaker in the palmar side of fingers than the other parts of hand. There should be additional study for evaluate thermal protection performance of firefighter clothes. And, further effort for reinforce palmar side of fingers of firefighter gloves should be done.

The Experimental Study of Electroacupuncture and Cervi Pantortichum Cornu Pharmacopuncture on Pain Decrease and Nerve Regeneration after Crush Injury of Sciatic Nerve (좌골신경 압좌 손상 후 전침 및 녹용 약침의 통증 감소와 신경 재생에 관한 실험적 연구)

  • Ahn, Hye-Lim;Yang, Mi-Sung;Shin, Mi-Sook;Choi, Jin-Bong;Kim, Sun-Jong
    • Journal of Korean Medicine Rehabilitation
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    • v.19 no.1
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    • pp.39-55
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    • 2009
  • Objectives : This study was designed to evaluate effects of electroacupuncture and Cervi Pantortichum Cornu pharmacopuncture on pain and nerve regeneration after crush injury of sciatic nerve in rats. Methods : We divided the subjects into 5 groups : control group, acupuncture treated group, electroacupuncture treated group, Cervi Pantortichum Cornu pharmacopuncture treated group, electroacupuncture and Cervi Pantortichum Cornu pharmacopuncture group. Hot plate test and degree of Substance P antibody in each group were observed at the 1st, 2nd, 3rd and 5th day. Sciatic function index and change of BDNF immunoreactivity had been estimated at the 7th, 14th, 21st day respectively. Atrophy of the gastrocnemius at the 21st day was observed. Results : All the experimental groups showed significant changes in hot plate test, degree of Substance P antibody, sciatic function index and change of BDNF immunoreactivity compared with control group. Especially, when electroacupuncture and Cervi Pantortichum Cornu pharmacopuncture used together, results were more effective than other groups. Recovery of the gastrocnemius was also the same. Conclusions : It is suggested that electroacupuncture and Cervi Pantortichum Cornu pharmacopuncture may play a significant role on pain decrease and nerve regeneration after crush injury of sciatic nerve in rats and these two treatments could be more effective when used together.

Antidepressant effect of the extracts of Subi-jeon, a Korean medicinal prescription (수비전(壽脾煎) 추출물의 항우울 효과에 관한 연구)

  • Han, Yoon-Seoung;Lee, Sang-Taek;Shim, Sang-Min;Kim, Geun-Woo;Kim, Ju-Ho;Kim, Kyeong-Ok;Kim, Hun-Il;Koo, Byung-Soo
    • Journal of Oriental Neuropsychiatry
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    • v.16 no.1
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    • pp.171-183
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    • 2005
  • Objective : The Korean famous medicinal prescription of Subi-jeon was investigated for their antidepressant effects by tail suspension test, hot plate test, reserpine-induced hypothermia test. In addition, the monoamine oxidase activity was determined in vivo. Methods : The methanol extract reduced dose-dependently the duration of immobility in the tail suspension test, by 31.4 and 34%(p<0.05) at doses of 500mg/kg and 1g/kg, respectively, compared with control group. In comparison with this, the effect of the water extract was very weak. Results : 1. In the hot plate test, the methanol extract potently increased the jump latency time(p<0.05) compared to the control group, exhibiting the inhibition rate of 197% and 256% at doses of 500mg/kg and 1g/kg(per os), respectively, which is more effective than the water extract. 2. Both extracts suppressed the fall of body temperature induced by reserpine(reserpine-induced hypothermia) in a dose-dependent manner, showing the less effect at lower doses and better effect at higher doses compared to the water extract. 3. Both extracts inhibited the brain monoamine oxidase activity in an in vivo assay compared to the control group, the activity of water extract was better than that of the methanol extract. Conclusion : The prescription of Subi-jeon can be useful for the prevention and treatment of depression.

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The Safety and Analgesic Effect of Datura Flos Pharmacopuncture in Sprague-Dawley Rats

  • Jun, Seungah;Lee, Yun Kyu;Lee, Bong Hyo;Kim, Jae Soo;Lee, Hyun-Jong
    • Journal of Acupuncture Research
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    • v.36 no.3
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    • pp.147-153
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    • 2019
  • Background: The aim of this study was to investigate the safety and analgesic effects of Datura Flos pharmacopuncture (DFP). Methods: The analgesic effects of DFP were assessed using mechanical (hot plate), chemical (formalin test), and thermal (von Frey filament test) pain tests. Forty male Sprague Dawley rats were assigned randomly into DFP (75 mg/kg, 150 mg/kg), lidocaine 0.5%, or normal saline group for treatment on Kl3. Gross pathology, histopathology, biochemistry and hematology were performed. Results: In the hot plate test, DFP at a high dose (HDDFP; 150 mg/kg) produced a significant analgesic effect, at 10 and 20-minutes post injection (p < 0.01). Low dose DFP (LDDFP; 75 mg/kg) also showed an analgesic effect at 10 minutes post injection (p < 0.01). In the formalin test, HDDFP produced an analgesic effect, for 0-10 and 10-20 minutes (p < 0.01) post treatment, whereas LDDFP showed analgesic effects between 10-20 minutes (p < 0.05). In the von Frey filament test, DF-H produced an analgesic effect, 10 (p < 0.01) and 20 minutes post treatment (p < 0.05). LDDFP showed analgesic effect at 10 minutes (p < 0.05). In the acupuncture response test, HDDFP produced an analgesic effect at 10 minutes post treatment (p < 0.05). DF-H did not cause any anatomical changes to the liver or kidney and there were no abnormalities in biochemistry or hematology. Conclusion: DF-H was not toxic and provided short term analgesia, suggesting it may be useful in the management of pain.

A Study on Selective Transfer and Reflow Process of Micro-LED using Micro Stamp (마이크로 스탬프를 이용한 Micro-LED 개별 전사 및리플로우 공정에 관한 연구)

  • Han, Seung;Yoon, Min-Ah;Kim, Chan;Kim, Jae-Hyun;Kim, Kwang-Seop
    • Tribology and Lubricants
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    • v.38 no.3
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    • pp.93-100
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    • 2022
  • Micro-light emitting diode (micro-LED) displays offer numerous advantages such as high brightness, fast response, and low power consumption. Hence, they are spotlighted as the next-generation display. However, defective LEDs may be created due to non-uniform contact loads or LED alignment errors. Therefore, a repair process involving the replacement of defective LEDs with favorable ones is necessitated. The general repair process involves the removal of defective micro-LEDs, interconnection material transfer, as well as new micro-LED transfer and bonding. However, micro-LEDs are difficult to repair since their size decreases to a few tens of micron in width and less than 10 ㎛ in thickness. The conventional nozzle-type dispenser for fluxes and the conventional vacuum chuck for LEDs are not applicable to the micro-LED repair process. In this study, transfer conditions are determined using a micro stamp for repairing micro-LEDs. Results show that the aging time should be set to within 60 min, based on measuring the aging time of the flux. Additionally, the micro-LEDs are subjected to a compression test, and the result shows that they should be transferred under 18.4 MPa. Finally, the I-V curves of micro-LEDs processed by the laser and hot plate reflows are measured to compare the electrical properties of the micro-LEDs based on the reflow methods. It was confirmed that the micro-LEDs processed by the laser reflow show similar electrical performance with that processed by the hot plate reflow. The results can provide guidance for the repair of micro-LEDs using micro stamps.